Heating apparatus



Jan. 12, 1965 L. PALMER ETAL 3,165,102

HEATING APPARATUS Original Filed Sept. 28, 1962 INVENTORS LANDON L. PALMER BY ERNEST w. WEAVER,5R mlmm-fyw AT TORNEYS;

United States Patent 3,165,102 EEATING APPARATUS Landon L. Palmer, 3535 Scarshorongh Road, Toledo, Ghio, and Ernest W. Weaver, r., Toledo, Ghio; said Weaver assignor to said Painter Continuation of application Ser. No. 226,838, Sept. 28, 1952. This application Mar. 11, 1964, Ser. No. 351,884 lairns. (Cl. l.2643) This invention relates to heating apparatus in general, and, in particular, to small portable stoves in which vaporizable liquid fuel is used. This application is a continuation of a copending application Serial No. 226,838, filed September 28, 1962 and assigned to the same assignee.

There have been a great many attempts in the past to improve the eiliciency of portable heating devices. For example, forced air feeds to increase the amount of cornbustible mixture available f r consumption have improved the portable heating devices, but have also increased the original cost, maintenance, bulk, and problems in handling and storing.

Others have improved the heating devices by utilizing absorption means for storing the fuel to provide a vapor feed to a mixing chamber. An example is shown in United States Patent No. 2,804,132, issued August 27, 1957. While the apparatus shown in the above-mentioned patent was a definite advance, difficulties are encountered in obtaining a desired heat energy level, since only one I flame results.

It is an object of this invention to provide an improved portable stove.

It is a further object of this invention to provide an im proved portable stove which can most efficiently vaporize and consume a quantity of liquid fuel.

A still further object of this invention is to provide a portable stove in which the fuel charge is temporarily absorbed into a porous body of the stove itself and is gradually vaporized into a mixing chamber with oxygen containing air coming from an air vent communicating with the outside atmosphere. In conjunction with the porous body containing the fuel charge there is utilized a chimney core made up of a porous insulating brick of a character that is virtually impervious to liquid flow therethrough but is pervious to vapor flow.

Accordingly, a stove embodying the above object features a body of porous material capable of absorbing liquid fuel. A vapor impervious container having side, top and bottom walls or surfaces surrounds and encloses the body of porous material. A mixing chamber is formed in the porous material adjacent to the bottom surface of the container. A vapor pervious chimney block is positioned in the body of porous material extending between the mixing chamber and the top surface of the container. A chimney passage is formed in the chimney block and the top surface of the container providing communication between the mixing chamber and the upper exterior of the container. A screen is disposed between the mixing chamber and the chimney passage. An air vent aperture is formed on the side surface of the container and an air passage is formed in the porous body of material between the mixing chamber and the air vent aperture. Means are provided for controlling the flow of air in the air passage which comprises an elongated plug to be positioned in the air vent aperture. The plug has a cross-sectional area at one end equal to the area of the air vent aperture. The cross-sectional area of the plug diminishes along the plugs length so that as the plug is withdrawn from the passage more air is allowed to flow through the passage from the exterior of the stove to the mixing chamber. The vapor pervious chimney block may be comprised of insulating fire brick. The body of porous material may be comprised of rock wool fibers.

3,1631% Patented Jan. 12, 19fi5 ICC Other objects, features and advantages of the invention will become apparent when the following description is taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a side elevatioal view of an upper element of the stove embodying the present invention;

FIG. 2 is a base element of the stove embodying the present invention, shown partly in section; and

FIG. 3 is an illustration of an air flow adjusting means to be used with the base element illustrated in FIG. 2.

Referring to the drawings and particularly to FIG. 2 thereof, a stove made in accordance with the present invention comprises a block of fuel absorbing material 20. A vapor impervious container, designated generally at 3%, having side walls or surfaces 31;, a top wall or surface 32 and a bottom wall or surface 33 is shown as surrounding and enclosing the body of porous material 2%. A mixing chamber ll is formed in the porous material 2% adjacent the bottom surface 33 of the container 30. A vapor pervious chimney block 50 is positioned in the body of the porous material 269 between the mixing chamber 40 and the top surface 32 of the container 39. A chimney passage, designated generally at 51, provides communication between the mixing chamber it? and the exterior of the container 3t through an aperture 34 formed in the top surface 32 of the container.

A screen 6t) is disposed between the mixing chamber it) and the chimney passage 51. An air vent aperture 35 is formed in the side wall or surface 31 of the container 3%. An air passage 70 is formed in the porous body of material 21) between the mixing chamber 40 and the air vent aperture 35 thereby providing means for air to flow from the exterior of the container 343 to the mixing chamber 40.

Means for regulating the flow of air in the air passage 70 is illustrated in the form of an elongated plug illus trated in FIG. 3. The plug 30 has a cross-sectional area 81 at one end which is equal to the cross-sectional area of the air Vent aperture 35'. The cross-sectional area of the plug 89 diminishes at 82, for example by a slanted oblique section removed from the normally cylindrical shape of the plug 8% along the plugs length. This allows the passage of more air through the aperture 35 as the plug St is withdrawn from the aperture 35.

Materials found particularly acceptable for the embodimerit shown herein for the body of porous material is rock wool fiber, and for the material of the chimney block an insulating fire brick material may be used (e.g. John Manville No. 1620 insulating brick).

Referring to FIG. 1 there is shown a wind and oxygen control element which also acts to support items to be heated by the stove. The upper element, designated gen erally at Ml, comprises an upwardly directed wall or extension 91, which extends from the periphery of the top surface 32 of the container 30. When the upper element 90 is slipped over the top of the container 30 the upper element 9i) rides on the identations 96 formed in the upwardly extending wall 91 which rest on the container 30.

.The extension M has a plurality of equally spaced elon gated slots 2 formed in the sides of the extension around the outside wall. A foraminous flue is suspended from brackets 94 so that it is positioned above the chimney passage 51 and is spaced from the top surface 32 of the container 30. The brackets 94 have raised ridges 95 formed on the top thereof to support items to be heated.

The invention is directed to the results obtained from the combination of the components hereinbefore described.

In operation the stove is first provided with a liquid fuel charge, preferably 95% alcohol fuel, by removing the upper element 90 and any sealing button that may have been inserted into the chimney passage 51. Fuel is [poured into the chimney passage 51; while the plug 84 is tightly inserted 'mto the air vent aperture 35 to prevent the fuel from draining out before it is absorbed. As inmediate advantage is shown in that-the stove does not require a separate filling port or aperture nor means to control a liquid flowing on the inside of a container, since the liquid fuel charge runs down the chimney passage 51 through the screen 64) into the mixing chamber 4! and is absorbed into the porous body of material 253.

Once a proper charge of liquid fuel has been placed into the chimney passage 51 the air vent 35 is opened by removal of the plug 80 to allow oxygen from the surrounding air to flow into the aperture 3:5 and through the air passage 70 to the mixing chamber 4%. The vapors provided by the liquid fuel absorbed in the porous body of material 2% are thus mixed with the oxygen from the air in the mixing chamber and become a combustible mixture. This combustible mixture rising through chimney passage 51, is then ignited.

It is important to note that there are then two flames burning during the operation of the stove. The first flame burns just above the screen es as the combustible mixture rises through the screen 6-9 from the mixing chamber 4%, the screen 6% preventing a flashback into the mixing chamber 40. A second flame burns at the top of the chimney passage 51 and the chimney aperture This combustible mixture is provided by vapors proceeding through the vapor pervious chimney block 559 from the porous body adjacent the chimney block 50 which are mixed 7 with pre-heated air that is flowing upward through the chimney passage 51 and from which the oxygen has not been entirely consumed by the flame just above the screen 69. An additional amount of oxygen comes from a how around the aperture 34 from the surrounding outside air to mix with the vapor mixture rising through passage 51.

The pre-heated mixture rising through the chimney passage 51 and the additional oxygen available from the exterior of the container provides a hotter and steadier flame when the base combination is utilized in conjunction with the upper element combination 9%. The wall 91, extending upwardly from the periphery of the top surface 32 of the container 30, has formed therein the elongated slots 92 to allow the passage of oxygen-containing air therethrough but to prevent a substantial wind from blowing the flame out. The foraminous flue 93 directs the heat vertically so that it is more efiiciently used, the forarninous portions of the flue allowing additional oxygen-containing air to be drawn in and consumed as a portion of the combustible mixture in the flame above the chimney passage 51. It is to be noted that the foraminous flue 93 is suspended in a position spaced from the top surface 32 of the container to provide an open space beneath the flue 93 around the periphery of the aperture 34 for a more rapid passage of oxygen-containing air. This sustains the flame and perfects the draft and blow torch ettect of the flame upwardly within the foraminous flue 93.

Thus the use of the upwardly extending wall and the forarninous line in conjunction with the cooperation of the components within the container 39 cooperate to form a vertically directed shaft of heat, the energy of which is not dissipated until it strikes and radiates over the bottom surface of the item being heated.

It has been found by experiment that applicants in- 41- vention comprising the cooperation of all the features described herein thus attains a markedly superior performance and comprises a considerable improvement over the prior art the steadiness of the flame and in the concentrated heat provided thereby from similar charges of fuel.

In conclusion, it is pointed out that while a preferred embodiment is illustrated, its specific details may be varied or modified without departing from the spirit of this invention.

Having described the invention, we claim:

I. A stove or the like comprising a body of porous material capable of absorbing liquid fuel; a vapor in:- pcrvious con= iner having side, top and bottom surfaces surrounding and enclosing said body of porous material; material bottom surface of said container; a vapor 1 block positioned in said body of porous aaerial extends g between said mixing chamber and a op surface of said container; a chimney passage being ormed in said chimney block and said top surface prodding communication between said mixing chamber and is e erior of said container; a screen disposed between said mixing chamber and said chimney passage; an air vent aperture being formed in a side surface of said conainer; air passage being formed in said porous body of material between said mixing chamber and said air g the flow of air said air passage.

2. A stove or the d e as defined in claim 1 and having eper element removably securable to said container; element comprising an upward extension from the periphery of said top surface of said container, said extension having a plurality of equally spaced, elongated vertical slots formed in the sides thereof; a forarninous flue disposed W1 n said upward extension and suspended above said chimney passage and said top surface of said container; and support means secured to said upward extension for receiving items to be heated.

3 A stove or the like as defined in claim 1 in which said air controlling means comprises an elongated plug for said air vent aperture; said plug having a cross-sectional area at one end equal to the area of sa d air vent aperture; said cross-sectional area of said plug diminishing along the plugs length to allow the passage of more air through said aperture as the plug is Withdrawn from the aperture.

4. A stove or the like as defined in claim 1 in which said vapor pervious chimney block is comprised of insulating fire brick.

5. A stove or the like as defined in claim 1 in which said body of porous material is comprised of rock wool fibers.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A STOVE OR THE LIKE COMPRISING A BODY OR POROUS MATERIAL CAPABLE OF ABSORBING LIQUID FUEL; A VAPOR IMPERVIOUS CONTAINER HAVING SIDE, TOP AND BOTTOM SURFACES SURROUNDING AND ENCLOSING SAID BODY OF POROUS MATERIAL; A MIXING CHAMBER BEING FORMED IN SAID POROUS MATERIAL ADJACENT SAID BOTTOM SURFACE OF SAID CONTAINER; A VAPOR PERVIOUS CHIMNEY BLOCK POSITIONED IN SAID BODY OF POROUS MATERIAL EXTENDING BETWEEN SAID MIXING CHAMBER AND A TOP SURFACE OF SAID CONTAINER; A CHIMNEY PASSAGE BEING FORMED IN SAID CHIMNEY BLOCK AND SAID TOP SURFACE PROVIDING COMMUNICATION BETWEEN AND SAID CHIMNEY PASSAGE; AN AIR THE EXTERIOR OF SAID CONTAINER; A SCREEN DISPOSED BETWEEN SAID MIXING CHAMBER AND SAID CHIMNEY PASSAGE; AN AIR VENT APERTURE BEING FORMED IN A SIDE SURFACE OF SAID CONTAINER; AN AIR PASSAGE BEING FORMED IN SAID POROUS BODY OF MATERIAL BETWEEN SAID MIXING CHAMBER AND SAID AIR VENT APERTURE; AND MEANS FOR CONTROLLING THE FLOW OF AIR IN SAID AIR PASSAGE. 